Atlantic and Pacific oscillations lost in the noise, say Mann & co. 

Posted: January 4, 2020 by oldbrew in Cycles, ENSO, modelling, Natural Variation, Ocean dynamics, research

Pacific Decadal Oscillation (PDO) [credit: NASA-JPL]

AMO & PDO – RIP. That’s the claim here anyway. Might be news to NASA and others.

Recently, meteorologists report that the Atlantic Multidecadal Oscillation (AMO) and the Pacific Decadal Oscillation (PDO) do not appear to exist, says Tech Explorist.

The discovery could have implications for both the validity of previous studies attributing past trends to these hypothetical natural oscillations and for the prospects of decade-scale climate predictability.

The discovery is based on observational data and climate model simulations, that shows there was no reliable proof for decadal or longer-term internal oscillatory signals that could be separated from climatic noise— arbitrary year to year variation.

The apparent main swaying is the well-known El Niño/Southern Oscillation (ENSO).

Scientists noted, “A distinct — 40 to 50-year timescale — a spectral peak that appears in global surface temperature observations appears to reflect the response of the climate system to a combination of anthropogenic and natural forcing rather than any intrinsic internal oscillation.”
. . .
Michael E. Mann, distinguished professor of atmospheric science at Penn State, said, “Given the current sophistication of climate models as seen in their ability to capture the El Niño/Southern Oscillation, we would expect to see consistent evidence for oscillations across a suite of climate models. We found no such evidence.”

Full article here.
– – –
Nature Communications: Absence of internal multidecadal and interdecadal oscillations in climate model simulations (Jan. 2020) – open access
[Authors: Michael E. Mann, Byron A. Steinman & Sonya K. Miller]
= = =

(some ritual ‘greenhouse’ propaganda near the end)

  1. tallbloke says:

    “According to the researchers, if the Atlantic Multidecadal or Pacific Decadal oscillations existed, there would be evidence for their existence across the suite of current state-of-the-art climate model simulations.”


    “Our climate models don’t mimic reality, therefore reality is wrong.”

  2. oldbrew says:

    B-b-but… ‘state-of-the-art’ models … 🙄 – the ones that are always wrong about warming?
    – – –
    Average spotless days, 6 solar cycles: 11-16 (1867 to 1933) = 793 per SC
    Average spotless days, 6 solar cycles: 17-22 (1933 to 1996) = 321 per SC
    SC 23-24 (1996 to date) still counting: average to date = 781 per SC

    17-22 period was ~3.5 years shorter than 11-16.

  3. hunterson7 says:

    This is crap to help shore up the CO2 obsessed consensus.

  4. tallbloke says:

    Getting a lot of retweets. 🙂

  5. oldbrew says:

    Climate modeller:

  6. stpaulchuck says:

    tallbloke says:
    January 4, 2020 at 12:11 pm

    bang on the nose Rog!

    this smells a whole lot like the disappearance of the Middle Ages Warm Period, the Roman Warm Period, etc., etc., that put the lie to the data fiddling graphs “proving” AGW (see ‘hockey stick’ for reference). Seems a last ditch effort to convince the ship Titanic BS’s passengers that all is well. “Who ya gonna believe, us or your lying thermometer?”

  7. craigm350 says:

    Reblogged this on WeatherAction News and commented:
    Your facts don’t care about his feelings! Where once a captain said Dive! , Dive! , Dive!, bloviating Captain Mann and his crew of beguilers shout Hide! Hide! Hide!. They seek to destroy that which they do not understand; as the many philistines, fanatical book and witch burners have in apparently less informed times. Unless, of course, Mann is rather overly showing his hand as a deeply political animal, in which case when Tim Ball said Mann belonged in Penn State he may well have been onto something.

  8. oldbrew says:

    Why don’t they point the finger at the climate models? Looks like they’re trying to salvage credibility for them when they clearly fall short. Computer says: no.

  9. Phoenix44 says:

    Just begging the question. They claim their models are good enough to show if they exist, and when the models show they don’t exist….

    But the models not showing them existing could also be proof the models aren’t good enough.

    Seriously, do Climate scientists (even “distinguished” ones), not have to follow logic?

  10. oldbrew says:

    The effects are the causes and models trump reality. That’s the logic 🤔

  11. ivan says:

    Has all the information and data necessary to reproduce the results been published or is this more Mann made globull warming (TM)?

    With M Mann as lead author it is automatically suspect.

  12. oldbrew says:

    ivan – yes, it’s all here:

    Or, that’s all you’re going to get.

  13. Ulric Lyons says:

    The AMO acts as an amplified negative feedback to changes in the solar wind, also controlling low cloud cover as a negative feedback. 1970’s global cooling was during stronger solar wind, and post 1995 global warming during weaker solar wind.

  14. oldbrew says:

    A model of future climate based on the observed orbital-climate relationships, but ignoring anthropogenic effects, predicts that the long-term trend over the next several thousand years is toward extensive Northern Hemisphere glaciation.

    Variations in the Earth’s Orbit: Pacemaker of the Ice Ages

    For 500,000 years, major climatic changes have
    followed variations in obliquity and precession.
    — J. D. Hays, John Imbrie, N. J. Shackleton

    Click to access Hays1976.pdf